Adding support to display data_src values, for events with data_src data
in sample.

Example:
  $ perf script
  ...
           rcuos/3    32 [002] ... 68501042 Local RAM hit|SNP None or Hit|TLB L1 or L2 hit|LCK No   ...
           rcuos/3    32 [002] ... 68100142 L1 hit|SNP None|TLB L1 or L2 hit|LCK No                 ...
           swapper     0 [002] ... 68100242 LFB hit|SNP None|TLB L1 or L2 hit|LCK No                ...
           swapper     0 [000] ... 68100142 L1 hit|SNP None|TLB L1 or L2 hit|LCK No                 ...
           swapper     0 [000] ... 50100142 L1 hit|SNP None|TLB L2 miss|LCK No                      ...
           rcuos/3    32 [002] ... 68100142 L1 hit|SNP None|TLB L1 or L2 hit|LCK No                 ...
   plugin-containe 16538 [000] ... 6a100142 L1 hit|SNP None|TLB L1 or L2 hit|LCK Yes                ...
           gkrellm  1736 [000] ... 68100242 LFB hit|SNP None|TLB L1 or L2 hit|LCK No                ...
           gkrellm  1736 [000] ... 6a100142 L1 hit|SNP None|TLB L1 or L2 hit|LCK Yes                ...

                                   ^^^^^^^^ ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
                             data_src value                     data_src translation
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1456303616-26926-14-git-send-email-jolsa@kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>